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Modelling and simulation of flight control electromechanical actuators with special focus on model architecting, multidisciplinary effects and power flows

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Chinese Journal of Aeronautics 2017年第1期30卷 47-65页

作者： fu Jian Jean-Charles Maré fu Yongling School of Mechanical Engineering and Automation Beihang University Beijing 100083 China Institut Clement Ader (CNRS UMR 5312) INSA-Toulouse Toulouse 31077 France

In the aerospace field, electromechanical actuators are increasingly being implemented in place of conventional hydraulic actuators. For safety-critical embedded actuation applications like flight controls, the use of electromechanical actuators introduces specific issues related to thermal balance, reflected inertia, parasitic motion due to compliance and response to failure. Unfortunately, the physical effects governing the actuator behaviour are multidisciplinary, coupled and nonlinear. Although numerous multi-domain and system-level simulation packages are now available on the market, these effects are rarely addressed as a whole because of a lack of scientific approaches for model architecting, multi-purpose incremental modelling and judicious model implementation. In this publication, virtual prototyping of electromechanical actuators is addressed using the Bond-Graph formalism. New approaches are proposed to enable incremental modelling,thermal balance analysis, response to free-run or jamming faults, impact of compliance on parasitic motion, and influence of temperature. A special focus is placed on friction and compliance of the mechanical transmission with fault injection and temperature dependence. Aileron actuation is used to highlight the proposals for control design, energy consumption and thermal analysis, power network pollution analysis and fault response.

关键词： Bond Graph Electro-hydrostatic actuator Electromechanical actuator More electric aircraft Modelling Power-by-wire Power loss Simulation

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建设工程全过程造价管理策略研究

价值工程 2025年第1期44卷 15-18页

作者：伏冬冬淮浙电力有限责任公司凤台发电分公司淮南232131

本研究旨在探讨建设工程项目全过程造价管理策略,以提高项目的经济效益和管理效率。研究内容涵盖了项目的决策、设计、招投标、施工及竣工各阶段的造价管理目标与策略。通过设计阶段风险评估与成本控制、招投标策略、施工进度与成本动... 详细信息

本研究旨在探讨建设工程项目全过程造价管理策略,以提高项目的经济效益和管理效率。研究内容涵盖了项目的决策、设计、招投标、施工及竣工各阶段的造价管理目标与策略。通过设计阶段风险评估与成本控制、招投标策略、施工进度与成本动态控制及竣工结算审核与后评估等方法,构建了全面的造价管理体系。研究结果表明,现代化先进技术以及先进工具,可以有效降低项目成本风险,提高造价管理的精度和效率。通过建立完善的审核和反馈机制,可以及时发现并解决各阶段的问题,优化项目管理流程。本研究为建设工程项目的造价管理提供了科学的理论依据和实践指导,有助于推动行业的管理水平提升,实现绿色建筑和可持续发展的目标。

关键词：建筑工程工程全过程造价管理工程效益

维普期刊数据库博看期刊

Uncovering the internal structure of five-fold twinned nanowires through 3D electron diffraction mapping

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Chinese Physics B 2020年第6期29卷 517-531页

作者： Xin fu GRINM Group Corporation Limited National Analysis and Testing Center for Nonferrous Metals and Electronic MaterialsBeijing 101400China Guobiao(Beijing)Testing&Certification Co. Ltd.Beijing 101400China China United Test&Certification Co. Ltd.Beijing 101400China General Research Institute for Nonferrous Metals Beijing 100088China

Five-fold twinned nanostructures are intrinsically strained or relaxed by extended defects to satisfy the space-filling *** both of metallic and semiconductor five-fold twinned nanostructures show inhomogeneity in their cross-sectional strain distribution,the evident strain concentration at twin boundaries in the semiconductor systems has been found in contrast to the metallic ***,a problem is raised how the chemical bonding characteristics of various five-fold twinned nanosystems affects their strain-relieving defect *** using three-dimensional(3D)electron diffraction mapping methodology,the intrinsic strain and the strain-relieving defects in a pentagonal Ag nanowire and a star-shaped boron carbide nanowire,both of them have basically equal radial twin-plane width about 30 nm,are nondestructively *** non-uniform strain and defect distribution between the five single crystalline segments are found in both of the five-fold twinned *** intensity fine structure analysis for the boron carbide five-fold twinned nanowire indicates the presence of high-density of planar defects which are responsible for the accommodation of the intrinsic angular ***,for the Ag five-fold twinned nanowire,the star-disclination strain field is still present,although is partially relieved by the formation of localized stacking fault layers accompanied by partial *** analysis suggests that the variety in the strain-relaxation ways for the two types of five-fold twinned nanowires could be ascribed to the large difference in shear modulus between the soft noble metal Ag and the superhard covalent compound boron carbide.

关键词： five-fold twinnining elastic strain structural relaxation electron diffraction mapping

Pretrained Models and Evaluation Data for the Khmer Language

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Tsinghua Science and Technology 2022年第4期27卷 709-718页

作者： Shengyi Jiang Sihui fu Nankai Lin Yingwen fu School of Information Science and Technology Guangdong University of Foreign StudiesGuangzhou 510000China Guangzhou Key Laboratory of Multilingual Intelligent Processing Guangdong University of Foreign StudiesGuangzhou 510000China

Trained on a large corpus,pretrained models(PTMs)can capture different levels of concepts in context and hence generate universal language representations,which greatly benefit downstream natural language processing(NLP)*** recent years,PTMs have been widely used in most NLP applications,especially for high-resource languages,such as English and ***,scarce resources have discouraged the progress of PTMs for low-resource ***-based PTMs for the Khmer language are presented in this work for the first *** evaluate our models on two downstream tasks:Part-of-speech tagging and news *** dataset for the latter task is *** demonstrate the effectiveness of the Khmer *** addition,we find that the current Khmer word segmentation technology does not aid performance *** aim to release our models and datasets to the community in hopes of facilitating the future development of Khmer NLP applications.

关键词： pretrained models Khmer language word segmentation part-of-speech(POS)tagging news categorization

Dynamics of 2×2 matrix non-Hermitian quantum systems on Bloch sphere

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Communications in Theoretical Physics 2024年第4期76卷 66-71页

作者： Libin fu Graduate School of China Academy of Engineering Physics Beijing 100193China

By casting evolution to the Bloch sphere, the dynamics of 2 × 2 matrix non-Hermitian systems are investigated in detail. This investigation reveals that there are four kinds of dynamical modes for such systems. The different modes are classified by different kinds of fixed points, namely,the elliptic point, spiral point, critical node, and degenerate point. The Hermitian systems and the unbroken PT non-Hermitian cases belong to the category with elliptic points. The degenerate point just corresponds to the systems with exceptional point(EP). The topological properties of the fixed point are also discussed. It is interesting that the topological charge for the degenerate point is two, while the others are one.

关键词： non-Hermitian quantum system two-level system dynamics on the Bloch sphere PT-symmetry fixed points

Simple generalized inductive limits of C^(*)-algebras

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Science China Mathematics 2021年第5期64卷 1029-1044页

作者： Xuanlong fu Department of Mathematics and the Research Center for Operator Algebras East China Normal UniversityShanghai 200062China

We give a necessary and sufficient condition where a generalized inductive limit becomes a simple C^(*)-algebra. We also show that if a unital C^(*)-algebra can be approximately embedded into some tensorially self absorbing C^(*)-algebra C(e.g., uniformly hyperfinite(UHF)-algebras of infinite type, the Cuntz algebra O_(2)),then we can construct a simple separable unital generalized inductive limit. When C is simple and infinite(*** infinite), the construction is also infinite(resp. properly infinite). When C is simple and approximately divisible, the construction is also approximately divisible. When C is a UHF-algebra and the connecting maps satisfy a trace condition, the construction has tracial rank zero.

关键词： C^(*)-algebras generalized inductive limit simplicity approximately divisible tracial rank zero

Bufo gargarizans:What’s in a Name?

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Asian Herpetological Research 2023年第3期14卷 246-255页

作者： Jinzhong fu Department of Integrative Biology University of GuelphGuelphOntario N1G 2W1Canada

The taxonomic status of Bufo species in East Asia,particularly those closely related to ***,has been controversial for over half a century,and recent molecular studies further fueled the *** ***,***,***,***,***,and *** constitute valid species or are geographic or ecological variants of *** is at the centre of the *** of these forms possess morphological diagnostic traits,but those differences are minimal and often *** data produced many contradictory *** of clear diagnostic characters,different usage or definition of various names,mis-identified specimens,limited amount of data or samples,and frequent inter-specific hybridization may all have contributed to the current *** contradiction may also result from differences between similarity-based clustering and gene tree-based branching ***,a dominant allopatric differentiation pattern within this species complex is apparent,and several regional population groups have been *** of the groups resemble old names(***,***),while others are *** groups may represent geographic or ecological variants,incipient species,or valid species,and the current data do not warrant a convincing taxonomic *** move forward,a single study with comprehensive sampling and genomic data is needed to establish a solid framework,which will define naturally existing population clusters/lineages,and detect their levels of divergence and approximate geographic *** and ecological examination will follow to understand their biology,determine their taxonomic status,and identify consistent diagnostic characters if necessary.

关键词： allopatric differentiation Bufo gargarizans species complex causes of controversy future directions population cluster taxonomic review

Study on detinning process of a reflow conductor roll

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Rare Metals 2005年第4期24卷 325-329页

作者： fu Hanguang DAI Mingshan fu Hanfeng Department of Mechanical Engineering Tsinghua University Beijing 100084 China Baoshan Iron ＆ Steel Co. Ltd. Shanghai 201900 China

Adhering tin is the main reason of a reflow conductor roll which works in an electroplating tin line （ETL）. A det- inning agent whose main composition is NaOH and KOH and assistant composition is Na2PbO2 or K2PbO2 and NaNO3 or NaNO2 has excellent detinning effects when the temperature of detinning solution is 40-80℃ and the temperature of the reflow conductor roll reaches 40-70℃. After the adhering tin layer of the reflow conductor roll is removed, the roughness of the reflow conductor roll can resume to 4.0 μm, its service life increases by 80%, and the repairing cost decreases by 90%.

关键词： electroplating tin reflow conductor roll detinning agent roughness

Ultrastrong MXene film bridged by liquid metal

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Science China Materials 2024年第12期67卷 4115-4116页

作者： Zhengyi fu State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

Two-dimensional(2D)titanium carbide(Ti3C2Tx)MXene nanosheets show promising mechanical and electrical properties,indicating great potential applications in aerospace and electronic devices,etc.[1,2].There are many assembling approaches including vacuum filtration,blade coating and layer-by-layer[3–5].However,it still remains a great challenge to realize the intrinsic performance of MXene nanosheets into macroscopic film due to low stress transfer efficiency,which usually is indued by the voids and misalignment during the assembling process[6].Thus,it remains a great challenge to assemble MXene nanosheets into high-performance macroscopic MXene films.

关键词： carbide coating film